import java.util.*;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * 有一个字符串，请将这个字符串右边加上一些字符，使其成为一个回文串
 * 如果有多种方案，请输出最短的回文串
 */
public class Test6 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        char[] chars = s.toCharArray();
        int i = 0;
        for (; i < chars.length; i++) {
            int left = i;
            int right = chars.length - 1;
            while(left < right) {
                if(chars[left] != chars[right]) {
                    break;
                }
                left++;
                right--;
            }
            if(left >= right) {
                break;
            }
        }
        StringBuilder sb = new StringBuilder(s);
        i -= 1;
        for(; i >= 0; i--) {
            sb.append(s.charAt(i));
        }
        System.out.println(sb.toString());
    }
}
